Predictive User Modeling with Actionable Attributes

Different machine learning techniques have been proposed and used for modeling individual and group user needs, interests and preferences. In the traditional predictive modeling instances are described by observable variables, called attributes. The goal is to learn a model for predicting the target variable for unseen instances. For example, for marketing purposes a company consider profiling a new user based on her observed web browsing behavior, referral keywords or other relevant information. In many real world applications the values of some attributes are not only observable, but can be actively decided by a decision maker. Furthermore, in some of such applications the decision maker is interested not only to generate accurate predictions, but to maximize the probability of the desired outcome. For example, a direct marketing manager can choose which type of a special offer to send to a client (actionable attribute), hoping that the right choice will result in a positive response with a higher probability. We study how to learn to choose the value of an actionable attribute in order to maximize the probability of a desired outcome in predictive modeling. We emphasize that not all instances are equally sensitive to changes in actions. Accurate choice of an action is critical for those instances, which are on the borderline (e.g. users who do not have a strong opinion one way or the other). We formulate three supervised learning approaches for learning to select the value of an actionable attribute at an instance level. We also introduce a focused training procedure which puts more emphasis on the situations where varying the action is the most likely to take the effect. The proof of concept experimental validation on two real-world case studies in web analytics and e-learning domains highlights the potential of the proposed approaches

Mining for knowledge to build decision support system for diagnosis and treatment of tinnitus

Tinnitus problems affect a significant portion of the population and are difficult to treat. Treatment processes are plentiful, yet not completely understood. In this dissertation, we present a knowledge discovery approach which can be used to build a decision support system for supporting tinnitus treatment. Our approach is based on a significant enlargement of the initial tinnitus database by adding many new tables containing new temporal features related to tinnitus evaluation and treatment outcome. Research presented in this thesis includes knowledge discovery with temporal, text, and quantitative data from a patient dataset of 3013 visits representing 758 unique patient tuples. Additionally, a new rule generating technique and clustering methods are presented and used to develop additional new temporal features and knowledge in this complex domain. Of particular interest is the role that emotions play in treatment success for tinnitus following the TRT method developed by Dr. Pawel Jastreboff. The ultimate goal of understanding the relationships among the treatment factors and measurements in order to better understand tinnitus treatment will result in the design foundations of a decision support system to aid in tinnitus treatment effectiveness

AUTOMATED META-ACTIONS DISCOVERY FOR PERSONALIZED MEDICAL TREATMENTS

Healthcare, among other domains, provides an attractive ground of work for knowl- edge discovery researchers. There exist several branches of health informatics and health data-mining from which we find actionable knowledge discovery is underserved. Actionable knowledge is best represented by patterns of structured actions that in- form decision makers about actions to take rather than providing static information that may or may not hint to actions. The Action rules model is a good example of active structured action patterns that informs us about the actions to perform to reach a desired outcome. It is augmented by the meta-actions model that rep- resents passive structured effects triggered by the application of an action. In this dissertation, we focus primarily on the meta-actions model that can be mapped to medical treatments and their effects in the healthcare arena. Our core contribution lies in structuring meta-actions and their effects (positive, neutral, negative, and side effects) along with mining techniques and evaluation metrics for meta-action effects. In addition to the mining techniques for treatment effects, this dissertation provides analysis and prediction of side effects, personalized action rules, alternatives for treat- ments with negative outcomes, evaluation for treatments success, and personalized recommendations for treatments. We used the tinnitus handicap dataset and the Healthcare Cost and Utilization Project (HCUP) Florida State Inpatient Databases (SID 2010) to validate our work. The results show the efficiency of our methods

Object-driven and temporal action rules mining

In this thesis, I present my complete research work in the field of action rules, more precisely object-driven and temporal action rules. The drive behind the introduction of object-driven and temporally based action rules is to bring forth an adapted ap- proach to extract action rules from a subclass of systems that have a specific nature, in which instances are observed from assumingly different distributions (defined by an object attribute), and in which each instance is coupled with a time-stamp. In previous publications, we proposed an object-independency assumption that suggests extracting patterns from subsystems defined by unique objects, and then aggregat- ing similar patterns amongst all objects. The motivation behind this approach is based on the fact that same-object observations share similar features that are not shared with other objects, and these features are possibly not explicitly included in our dataset. Therefore, by individualizing objects prior to calculating action rules, variance is reduced, and over-fitting is potentially avoided. In addition to the object- independency assumption, temporal information is exploited by taking into account only the state transitions that occurred in the valid direction.j The common nature of object-driven and temporal action rules made us believe that this work is general enough to solve a diverse fields of areas where it is highly needed. In our case study, we show how our approach was applied to an information system of hypernasality patients; our results were further investigated by physicians collaborators to confirm them